The present applicant has proposed a card reader which is capable of discriminating whether a card taken into the card reader is a card having a normal shape which is in compliance with ISO (JIS) standards or a nonstandard card having a special shape (see, for example, Japanese Patent Laid-Open No. 2005-165625).
In the card reader described in the above-mentioned Patent Reference, a card having a special shape and a card having a normal shape are discriminated by using a pre-head and a card detect switch which are disposed in the vicinity of a card insertion port. Specifically, in this card reader, a card having a normal shape which is formed with a magnetic stripe 2a on its surface is discriminated from a card which is formed with a magnetic stripe 2a on its surface and which is having a special shape, like a card 2A shown in FIG. 10(A), where one of rear side corners in a card taking-in direction is formed in a curved shape having a large radius of curvature.
In recent years, nonstandard cards having various special shapes have been circulating on the market. For example, the following cards have begun to circulate on the market, i.e., a card 2B (see FIG. 10(B)) having a similar outward shape to the card 2A and provided with an IC chip 2b but without a magnetic stripe 2a, a card 2C (see FIG. 10(C)) which is provided with an IC chip 2b but without a magnetic stripe 2a and which is formed in a semicircular shape at one end in a longitudinal direction of the card, in other words, both rear side corners are formed in a curved shape having a large radius of curvature, and a card 2D (see FIG. 10(D)) which is provided with an IC chip 2b but without a magnetic stripe 2a and which is formed in a curved shape at both ends in a longitudinal direction of the card. Therefore, a card reader is desired on the market which is capable of discriminating various cards having such special shapes and, when the card is judged to have a predetermined special shape, the card is taken into the inside to perform a predetermined processing.
However, the card reader described in the above-mentioned Patent Reference cannot discriminate the cards 2B through 2D having no magnetic stripe 2a to be a card having a predetermined special shape. Further, even when the magnetic stripe 2a is formed on a card, the card reader described in the above-mentioned Patent Reference cannot discriminate whether the card is a card having a predetermined special shape or not unless the magnetic stripe 2a is formed over a length in compliance with the standards. In other words, it is difficult that the card reader described in the above-mentioned Patent Reference discriminates various cards having special shapes.